large-file-splitter 0.2.0

The tool considers a file so large that it does not fit in memory as a single string and performs a split process of the string. The tool stores the result as separate files.

large_file_splitter

下の方に日本語の説明があります

Overview

• The tool considers a file so large that it does not fit in memory as a single string and performs a split process of the string. The tool stores the result as separate files.
• under construction

Usage

import large_file_splitter

# Split a large file [large_file_splitter].
large_file_splitter.split(
	"dummy_large_file.txt", # File to be split
	split_str = "SPLIT_MARK\r\n", # Split string (For convenience of splitting, it is processed as binary internally, so setting this to a single character is not recommended because it may lead to erroneous splitting of multi-byte characters, etc.)
	div_mode = "start", # mode for handling split strings (delete: split string is not included in output; start: split string is concatenated at the beginning of the next chunk; end: split string is concatenated at the end of the previous chunk)
	output_filename_frame = "./output/div_%d.txt", # Template for output filename (an integer value is automatically inserted for %d)
	cache_size = 10 * 1024 * 1024 # Specify the size of the chunk of data to work with in memory (in bytes; memory capacity must be at least several times this size.)
)

Example of usage (in the context of a for loop)

import large_file_splitter

# Split a large file (for loop version) [large_file_splitter]
for one_str in large_file_splitter.for_split(
	"dummy_large_file.txt",	# Target file for splitting
	split_str = "SPLIT_MARK\r\n",	# Split string (for internal processing, it is treated as binary, so it is not recommended to make this a single character, etc., as it may lead to incorrect splitting of multi-byte characters)
	div_mode = "start",	# Mode of handling the split string (delete: split string is not included in the output; start: split string is joined to the beginning of the next block; end: split string is joined to the end of the previous block)
	cache_size = 1024	# Specifies the size of the data block to work with in memory (in bytes; at least this multiple of memory capacity is required)
):
	# Some processing using the string `one_str`
	print(one_str)

概要

• メモリに乗らないほど巨大なファイルを一つの文字列とみなし、文字列のsplit処理を実施。その結果を別々のファイルとして格納するツール。
• 説明は執筆中です

使用例

import large_file_splitter

# 巨大ファイルの分割 [large_file_splitter]
large_file_splitter.split(
	"dummy_large_file.txt",	# 分割対象ファイル
	split_str = "SPLIT_MARK\r\n",	# 分割文字列 (分割の都合上内部ではbinaryとして処理するので、ここを一文字等にするのは、マルチバイト文字等の誤分割に繋がる可能性があるため非推奨)
	div_mode = "start",	# 分割文字列の扱いのモード (delete: 分割文字列は出力に含まない; start: 分割文字列は次の塊の先頭に結合される; end: 分割文字列は前の塊の末尾に結合される)
	output_filename_frame = "./output/div_%d.txt",	# 出力先ファイル名のテンプレート (%dのところは自動で整数値が挿入される)
	cache_size = 10 * 1024 * 1024	# メモリで作業するデータ塊の大きさの指定 (バイト単位; メモリ容量は少なくともこの数倍は必要)
)

使用例 (for文脈での利用)

import large_file_splitter

# 巨大ファイルの分割 (for文脈バージョン) [large_file_splitter]
for one_str in large_file_splitter.for_split(
	"dummy_large_file.txt",	# 分割対象ファイル
	split_str = "SPLIT_MARK\r\n",	# 分割文字列 (分割の都合上内部ではbinaryとして処理するので、ここを一文字等にするのは、マルチバイト文字等の誤分割に繋がる可能性があるため非推奨)
	div_mode = "start",	# 分割文字列の扱いのモード (delete: 分割文字列は出力に含まない; start: 分割文字列は次の塊の先頭に結合される; end: 分割文字列は前の塊の末尾に結合される)
	cache_size = 1024	# メモリで作業するデータ塊の大きさの指定 (バイト単位; メモリ容量は少なくともこの数倍は必要)
):
	# 文字列 `one_str` を用いた何らかの処理
	print(one_str)